Noble metals are resistant to corrosion and oxidation; and include ruthenium, rhodium, palladium, silver, osmium, iridium, platinum and gold. The electrical, chemical and physical properties of noble metals may make them particularly well-suited for some applications in integrated circuit fabrication. For instance, nanoclusters of noble metals may be well-suited for utilization as charge-trapping centers of non-volatile memory cells.
A problem in utilizing noble metals is that their resistance to corrosion and oxidation may render it difficult to pattern and otherwise fabricate the metals utilizing conventional methodologies. For instance, a chemical commonly utilized for etching noble metals is aqua regia—which is a highly corrosive mixture of nitric acid and HCl. Unfortunately, aqua regia will attack numerous compositions associated with integrated circuitry, and thus it may not be suitable to utilize aqua regia during integrated circuit fabrication.
It would be desirable to develop new methods for patterning noble metals during integrated circuit fabrication.